A quote from Robert E. Lee

I found this excerpted from a letter between the great general and Charles Marshall, dated 1866, and thought it was appropriate for contemporary situation(s):

"The march of Providence is so slow and our desires so impatient; the work of progress is so immense and our means of aiding it so feeble; the life of humanity is so long, that of the individual so brief, that we often see only the ebb of the advancing ways, and are thus discouraged. It is history that teaches us to hope."